Information-flow types for homomorphic encryptions

Cédric Fournet, Jérémy Planul, Tamara Rezk
2011 Proceedings of the 18th ACM conference on Computer and communications security - CCS '11  
We develop a flexible information-flow type system for a range of encryption primitives, precisely reflecting their diverse functional and security features. Our rules enable encryption, blinding, homomorphic computation, and decryption, with selective key re-use for different types of payloads. We show that, under standard cryptographic assumptions, any well-typed probabilistic program using encryptions is secure (that is, computationally non-interferent) against active adversaries, both for
more » ... nfidentiality and integrity. We illustrate our approach using ElGamal and Paillier encryption. We present two applications of cryptographic verification by typing: (1) private search on data streams; and (2) the bootstrapping part of Gentry's fully homomorphic encryption. We provide a prototype typechecker for our system.
doi:10.1145/2046707.2046747 dblp:conf/ccs/FournetPR11 fatcat:zxpcuvctdncbhc5tfmwisr23fq