状态硬件复位硬件对称的假设From Stateful Hardware to Resettable Hardware Using Symmetric Assumptions.pdf

From Stateful to Resettable Hardware Using Symmetric Assumptions Nico D枚ttling, Daniel Kraschewski, J枚rn M眉ller-Quade Tobias Nilges Aarhus University, TNG Technology Consulting GmbH, Karlsruhe Institute of Technology General Setting Alice Bob 肀犿睋 螤 鈩 鈩 is arbitrary functionality, e.g. OT, Commitment鈥? Motivation 鈥 UC-secure protocols impossible without setup-assumptions 鈥 [Katz07] introduced tamper- proof hardware as a UC setup- assumption 鈥 Stateful token: statistically UC- secure OT is possible [DKM11] What about resettable tokens? 鈥 Still powerful, but most statistically secure protocols impossible [GIMS10] 鈥 Feasibility of NI-2PC for resettable functionalities shown by [DMMN13] 鈥 Open question: relation between stateful and resettable token protocols wrt feasibility? Our Results 鈥 All protocols based on stateful tokens can be transformed to use resettable tokens 鈥 General compiler for UC-secure protocols 鈥 Requires interaction 鈥 Requires computational assumptions (only OWF!) or additional setup Basic Idea 鈥 Shift state from token to Alice: 鈥 Alice authenticates inputs 鈥 Bob sends authenticated value to token 鈥 Problem: Alice must not learn Bob鈥榮 inputs 鈥 Solution: 鈥 Alice authenticates encoding of input 鈥 Bob provides authentication and decoding information Blueprint of Our Approach Alice Bob 鈥 Generate token program 饊亣 Token 鈥 Interaction wit