Quantifying information flow for dynamic secrets

Abstract—A metric is proposed for quantifying leakage of information about secrets and about how secrets change over time. The metric is used with a model of information flow for probabilistic, interactive systems with adaptive adversaries. The model and metric are implemented in a probabilistic program-ming language and used to analyze several examples. The analysis demonstrates that adaptivity increases information flow. Keywords—dynamic secret, quantitative information flow, prob-abilistic programming, gain function, vulnerability I