Policy-based signature scheme from lattices

Swati Rawal, Sahadeo Padhye, Debiao He

Ziyuan Liu, Jen-Chieh Hsu, Raylin Tso +1 more

Policy-controlled signature (PCS) was introduced by Pairat Thorncharoensri et al. at ICICS 2009, and improved at Computer Standards & Interfaces 2017. In this type of digital signature, signer can sign a message with some policies. Any verifier who does not satisfies the policies cannot verify the message. They also extended the notion of policy-controlled signature, and called it "universal policy-controlled signature". In their extended notion, they improve the flexibility of the PCS scheme by allowing a third party to equip the signature with policy, rather than the signer. In this work, we use the recent techniques in lattice to construct policy- controlled based signature from NTRU lattice. In particular, we adapt Léo Ducas et al.'s encryption and signature protocol on lattice (ASIACRYPT 2014), and combine them with Pairat Thorncharoensri et al.'s work to satisfy the properties of policy-controlled signature. Our contribution is developing the first quantum- resistant schema based on the policy-controlled signature.

Rachid El Bansarkhani, Johannes A Buchmann

Yongtao Wang

A lattice ciphertext policy attribute based encryption (CP-ABE) scheme is presented, in which the ciphertext policy achieved is the AND-gates on multi-valued attributes. The previous construction with AND-gates on multi-valued attributes as ciphertext policy is based on bilinear paring technology. In this paper, inspired by the recent progress of lattice identity based encryption scheme, we achieve this access structure from lattice technology. There are two constructions given, and both of them can be viewed as an extension and generalization of the lattice identity based encryption schemes proposed by Agrawal et al., respectively. In addition, our constructions are shown to be secure under the learning with errors assumption in the standard model.

Zechao Liu, Zoe L. Jiang, Xu An Wang +2 more

Ciphertext policy attribute-based encryption (CP-ABE) is a promising cryptographic technology that provides fine-grained access control as well as data confidentiality. It enables one sender to encrypt the data for more receivers, and to specify a policy on who can decrypt the ciphertext using his/her attributes alone. However, most existing ABE schemes are constructed on bilinear maps and they cannot resist quantum attacks. In this paper, we propose a multi-authority CP-ABE (MA-CPABE) scheme on ideal lattices which is still secure in post-quantum era. On one hand, multiple attribute authorities are required when user's attributes cannot be managed by a central authority. On the other hand, compared with generic lattice, the ideal lattice has extra algebraic structure and can be used to construct more efficient cryptographic applications. By adding some virtual attributes for each authority, our scheme can support flexible threshold access policy. Security analysis shows that the proposed scheme is secure against chosen plaintext attack (CPA) in the standard model under the ring learning with errors (R-LWE) assumption.

Miaomiao Tian, Liusheng Huang