Relationship between Standard Model Plaintext Awareness and Message Hiding

Abstract

Recently, Bellare and Palacio defined the plaintext awareness (PA-ness) in the standard model. In this paper, we study the relationship between the standard model PA-ness and the property about message hiding, that is, IND-CPA. Although these two notions seem to be independent at first glance, we show that PA-ness in the standard model implies the IND-CPA security if the encryption function is oneway. By using this result, we also showed that “PA+Oneway⇒IND-CCA2.” We also show that the computational PA-ness notion is strictly stronger than the statistical one.