**Predicate Encryption for Circuits from LWE**

*Sergey Gorbunov and Vinod Vaikuntanathan and Hoeteck Wee*

**Abstract: **In predicate encryption, a ciphertext is associated with descriptive
attribute values $x$ in addition to a plaintext $\mu$, and a secret key is associated with a predicate $f$. Decryption returns plaintext
$\mu$ if and only if $f(x) = 1$. Moreover, security of predicate
encryption guarantees that an adversary learns nothing about the attribute $x$ or the plaintext $\mu$ from a ciphertext, given arbitrary many secret keys that are not authorized to decrypt the ciphertext individually.

We construct a leveled predicate encryption scheme for all circuits, assuming the hardness of the subexponential learning with errors (LWE) problem. That is, for any polynomial function $d = d(\secp)$, we construct a predicate encryption scheme for the class of all circuits with depth bounded by $d(\secp)$, where $\secp$ is the security parameter.

**Category / Keywords: **Predicate Encryption, Circuits, LWE, Lattices

**Date: **received 13 Jan 2015, last revised 13 Jan 2015

**Contact author: **sergeyg at mit edu

**Available format(s): **PDF | BibTeX Citation

**Version: **20150114:165118 (All versions of this report)

**Short URL: **ia.cr/2015/029

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