On the Selective Opening Security of Practical Public-Key Encryption Schemes

We show that two well-known and widely employed public-key encryption schemes – RSA Optimal Asymmetric Encryption Padding (RSA-OAEP) and Diffie-Hellman Integrated Encryption Scheme (DHIES), instantiated with a one-time pad, – are secure under (the strong, simulation-based security notion of) selective opening security against chosen-ciphertext attacks in the random oracle model. Both schemes are obtained via known generic transformations that transform relatively weak primitives (with security in the sense of one-wayness) to IND-CCA secure encryption schemes. We also show a similar result for the well-known Fujisaki-Okamoto transformation that can generically turn a one-way secure public key encryption system and a one-time pad into a INDCCA-secure public-key encryption system. We prove that selective opening security comes for free in these transformations. Both DHIES and RSA-OAEP are important building blocks in several standards for public key encryption and key exchange protoc...

• Type: Journal
• Year: 2015
• Where: PKC
• Authors: Felix Heuer, Tibor Jager, Eike Kiltz, Sven Schäge
• Keywords: Cryptology, PKC 2015