Hiding Information in Completeness Holes: New Perspectives in Code Obfuscation and Watermarking

In this paper we show how abstract interpretation, and more specifically completeness, provides an adequate model for reasoning about code obfuscation and watermarking. The idea is that making a program obscure, or equivalently hiding information in it, corresponds to force an interpreter (the attacker) to become incomplete in its attempts to extract information about the program. Here abstract interpretation provides the model of the attacker (malicious host) and abstract interpretation transformers provide driving methods for understanding and designing new obfuscation and watermarking strategies: Obfuscation corresponds to make the malicious host incomplete and watermarking corresponds to hide secrets where incomplete attackers cannot extract them unless some secret key is given.