Private Functional Signatures: Definition and Construction
Paper in proceedings, 2018

In this paper, we introduce a new cryptographic primitive: private functional signatures, where functional signing keys skffor functions f derived from master signing key msk which can be used to sign any message, allow one to sign any message in the range of the underlying function f. Besides, there is an encryption algorithm which takes as input the master secret key msk to produce a ciphertext cxfor message x. And the signing algorithm applies a signing key skfon the ciphertext cxto produce a signature σf(x)on the result f(x). We also formalize the security notions of private functional signatures. Furthermore, we provide a general compiler from any (single-key) symmetric-key predicate encryption scheme into a single-key private functional signature scheme. By instantiating our construction with schemes for symmetric-key predicate encryption, we obtain private functional signature schemes based on a variety of assumptions (including the LWE assumption, simple multilinear-maps assumptions, obfuscation assumptions, and even the existence of any one-way function) offering various trade-offs between security and efficiency.

Functional encryption

Predicate encryption

Functional signature


Shimin Li

Chinese Academy of Sciences

Bei Liang

Chalmers, Computer Science and Engineering (Chalmers), Networks and Systems (Chalmers)

Rui Xue

Chinese Academy of Sciences

Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

03029743 (ISSN) 16113349 (eISSN)

Vol. 10946 284-303

23rd Australasian Conference on Information Security and Privacy, ACISP 2018
Wollongong, Australia,

Subject Categories

Algebra and Logic

Computational Mathematics

Mathematical Analysis



More information

Latest update