5Gen

Abstract

Secure multilinear maps (mmaps) have been shown to have remarkable applications in cryptography, such as multi-input functional encryption (MIFE) and program obfuscation. To date, there has been little evaluation of the performance of these applications. In this paper we initiate a systematic study of mmap-based constructions. We build a general framework, called 5Gen, to experiment with these applications. At the top layer we develop a compiler that takes in a high-level program and produces an optimized matrix branching program needed for the applications we consider. Next, we optimize and experiment with several MIFE and obfuscation constructions and evaluate their performance. The 5Gen framework is modular and can easily accommodate new mmap constructions as well as new MIFE and obfuscation constructions, as well as being an open-source tool that can be used by other research groups to experiment with a variety of mmap-based constructions.1 The name 5Gen comes from the fact that multilinear maps can be considered the "fifth generation" of cryptography, where the prior four are: symmetric key, public key, bilinear maps, and fully homomorphic encryption.

Layered obfuscation: a taxonomy of software obfuscation techniques for layered security

“…From the theoretical perspective, scientists have already found an algorithm (i.e., graded encoding) which can obfuscate all programs with a compelling security property: indistinguishability (Garg et al 2013a;Zimmerman 2015;Lewi et al 2016). Since such results may confuse readers, next, we clarify the gaps between such theoretical research and real-world obfuscation problems with a sample graded encoding mechanism.…”

Self-Processing Private Sensor Data via Garbled Encryption

“…Furthermore, known constructions of secretkey MiFE for bounded ciphertexts from standard assumptions [4,14] require non-black-box use of cryptographic primitives and are therefore unexplored with respect to implementability and efficiency. Constructions of secret-key MiFE from nonstandard multilinear maps [25] take 4 minutes running on a 32-core server for function evaluations on 4.7 GB ciphertexts, while only achieving security with respect to security parameter λ = 80. As a result, despite its immense potential, MiFE has so far had limited impact on the security world and does not give a practical solution to the proposed problem.…”

“…MiFE was first introduced in [19]. Constructing such schemes and variants has been a topic of much research in recent years [3,4,12,14,15,17,25]. [28] introduced a relaxation of functional encryption, called controlled functional encryption, in order to obtain an implementable variant of FE.…”