Paper 2018/529
Trapdoor Functions from the Computational Diffie-Hellman Assumption
Sanjam Garg and Mohammad Hajiabadi
Abstract
Trapdoor functions (TDFs) are a fundamental primitive in cryptography. Yet, the current set of assumptions known to imply TDFs is surprisingly limited, when compared to public-key encryption. We present a new general approach for constructing TDFs. Specifically, we give a generic construction of TDFs from any Hash Encryption (Döttling and Garg [CRYPTO '17]) satisfying a novel property which we call recyclability. By showing how to adapt current Computational Diffie-Hellman (CDH) based constructions of hash encryption to yield recyclability, we obtain the first construction of TDFs with security proved under the CDH assumption. While TDFs from the Decisional Diffie-Hellman (DDH) assumption were previously known, the possibility of basing them on CDH had remained open for more than 30 years.
Note: Fixed a typo in the abstract.
Metadata
- Available format(s)
- Category
- Public-key cryptography
- Publication info
- A minor revision of an IACR publication in CRYPTO 2018
- Keywords
- Trapdoor FunctionsComputational Diffie-Hellman Assumption
- Contact author(s)
- mdhajiabadi @ berkeley edu,sanjamg @ berkeley edu
- History
- 2018-06-29: last of 2 revisions
- 2018-06-04: received
- See all versions
- Short URL
- https://ia.cr/2018/529
- License
-
CC BY