## CryptoDB

### Jie Chen

#### Publications

Year
Venue
Title
2021
PKC
In this paper, we propose the first generic framework for attribute-based encryptions (ABE) with master-secret-key-dependent-message security (mKDM security) for affine functions via predicate encodings by Chen, Gay and Wee [Eurocrypt 2015]. The construction is adaptively secure under standard $k$-Lin assumption in prime-order bilinear groups. By this, we obtain a set of new mKDM-secure ABE schemes with high expressiveness that have never been reached before: we get the first hierarchical IBE (HIBE) scheme and the first ABE scheme for arithmetic branching program (ABP) with mKDM security for affine functions. Thanks to the expressiveness (more concretely, delegability like HIBE), we can obtain mKDM-secure ABE against chosen-ciphertext attack (i.e., CCA security) via a classical CPA-to-CCA transformation that works well in the context of mKDM.
2018
EUROCRYPT
2018
ASIACRYPT
In this work, we propose two IPE schemes achieving both adaptive security and full attribute-hiding in the prime-order bilinear group, which improve upon the unique existing result satisfying both features from Okamoto and Takashima [Eurocrypt ’12] in terms of efficiency. Our first IPE scheme is based on the standard $k\textsc {-lin}$ assumption and has shorter master public key and shorter secret keys than Okamoto and Takashima’s IPE under weaker ${\textsc {dlin} }=2\textsc {-lin}$ assumption.Our second IPE scheme is adapted from the first one; the security is based on the ${\textsc {xdlin}}$ assumption (as Okamoto and Takashima’s IPE) but now it also enjoys shorter ciphertexts. Technically, instead of starting from composite-order IPE and applying existing transformation, we start from an IPE scheme in a very restricted setting but already in the prime-order group, and then gradually upgrade it to our full-fledged IPE scheme. This method allows us to integrate Chen et al.’s framework [Eurocrypt ’15] with recent new techniques [TCC ’17, Eurocrypt ’18] in an optimized way.
2017
PKC
2017
ASIACRYPT
2016
PKC
2016
ASIACRYPT
2015
EUROCRYPT
2013
CRYPTO

Asiacrypt 2020
PKC 2019
PKC 2018
Asiacrypt 2017

#### Coauthors

Zhenfu Cao (2)
Xiaolei Dong (2)
Shengyuan Feng (1)
Romain Gay (1)
Junqing Gong (7)
Lucas Kowalczyk (1)
Shaohua Tang (1)
Hoeteck Wee (4)
Jian Weng (1)