waters11

Ciphertext-Policy ABE: Expressive and Efficient (Waters11)

Authors: Brent Waters

Title: “Ciphertext-Policy Attribute-Based Encryption: An Expressive, Efficient, and Provably Secure Realization”

Published in: Public Key Cryptography (PKC), 2011

Available from: https://doi.org/10.1007/978-3-642-19379-8_4

Notes: Asymmetric version of the scheme in Section 3

Scheme Properties

• Type: ciphertext-policy attribute-based encryption

• Setting: Pairing groups

• Assumption: Decisional Parallel Bilinear Diffie-Hellman Exponent

Implementation

Authors:

Shashank Agrawal

Date:

05/2016

class waters11.Waters11(group_obj, uni_size, verbose=False)

Bases: ABEnc

decrypt(pk, ctxt, key)

Decrypt ciphertext ctxt with key key.

encrypt(pk, msg, policy_str)

Encrypt a message M under a monotone span program.

keygen(pk, msk, attr_list)

Generate a key for a set of attributes.

setup()

Generates public key and master secret key.