Authors
Saikrishna Badrinarayanan, Aayush Jain, Nathan Manohar, Amit Sahai
Publication date
2020
Conference
Advances in Cryptology–ASIACRYPT 2020: 26th International Conference on the Theory and Application of Cryptology and Information Security, Daejeon, South Korea, December 7–11, 2020, Proceedings, Part III 26
Pages
120-150
Publisher
Springer International Publishing
Description
Motivated by what we call “honest but lazy” parties in the context of secure multi party computation, we revisit the notion of multi-key FHE schemes (MFHE). In MFHE, any message encrypted using a public key can be “expanded” so that the resulting ciphertext is encrypted with respect to a set of public keys . Such expanded ciphertexts can be homomorphically evaluated with respect to any circuit to generate a ciphertext . Then, this ciphertext can be partially decrypted using a secret key (corresponding to the public key ) to produce a partial decryption . Finally, these partial decryptions can be combined to recover the output. However, this definition of MFHE works only for n-out-of-n access structures and, thus, each node in the system is a point of failure. In the context of “honest but lazy” parties, it is necessary to be able to decrypt even when only given a subset of partial …
Total citations
2019202020212022202320244398103
Scholar articles
S Badrinarayanan, A Jain, N Manohar, A Sahai - Advances in Cryptology–ASIACRYPT 2020: 26th …, 2020