A Space-Aware Bytecode Verifier for Java Cards

The bytecode verification is a key point of the security chain of the Java Platform. This feature is optional in many embedded devices since the memory requirements of the verification process are too high. In this paper we propose a verification algorithm that remarkably reduces the use of the memory by performing the verification during multiple specialized passes. The algorithm reduces the type encoding space by operating on different abstractions of the domain of types. The results of the experiments show that this bytecode verification can be performed directly on small memory systems.