International Association for Cryptologic Research

International Association
for Cryptologic Research


Paper: New Constructions of Identity-Based and Key-Dependent Message Secure Encryption Schemes

Nico Döttling
Sanjam Garg
Mohammad Hajiabadi
Daniel Masny
DOI: 10.1007/978-3-319-76578-5_1
Search ePrint
Search Google
Conference: PKC 2018
Abstract: Recently, Döttling and Garg (CRYPTO 2017) showed how to build identity-based encryption (IBE) from a novel primitive termed Chameleon Encryption, which can in turn be realized from simple number theoretic hardness assumptions such as the computational Diffie-Hellman assumption (in groups without pairings) or the factoring assumption. In a follow-up work (TCC 2017), the same authors showed that IBE can also be constructed from a slightly weaker primitive called One-Time Signatures with Encryption (OTSE).In this work, we show that OTSE can be instantiated from hard learning problems such as the Learning With Errors (LWE) and the Learning Parity with Noise (LPN) problems. This immediately yields the first IBE construction from the LPN problem and a construction based on a weaker LWE assumption compared to previous works.Finally, we show that the notion of one-time signatures with encryption is also useful for the construction of key-dependent-message (KDM) secure public-key encryption. In particular, our results imply that a KDM-secure public key encryption can be constructed from any KDM-secure secret-key encryption scheme and any public-key encryption scheme.
  title={New Constructions of Identity-Based and Key-Dependent Message Secure Encryption Schemes},
  booktitle={Public-Key Cryptography – PKC 2018},
  series={Public-Key Cryptography – PKC 2018},
  author={Nico Döttling and Sanjam Garg and Mohammad Hajiabadi and Daniel Masny},