On the Composability of Statistically Secure Random Oblivious Transfer
This work addresses the composability of secure protocols for cryptography researchers, providing a foundational result that enhances the usability of existing oblivious transfer methods in broader secure applications.
The paper tackles the problem of ensuring that statistically secure random oblivious transfer protocols remain secure when composed arbitrarily, showing that protocols based on two-party stateless primitives are statistically universally composable, which allows previous protocols proven under weaker definitions to be used in secure applications without compromising security.
We show that stand-alone statistically secure random oblivious transfer protocols based on two-party stateless primitives are statistically universally composable. I.e. they are simulatable secure with an unlimited adversary, an unlimited simulator and an unlimited environment machine. Our result implies that several previous oblivious transfer protocols in the literature which were proven secure under weaker, non-composable definitions of security can actually be used in arbitrary statistically secure applications without lowering the security.