abenc_adapt_hybrid

Hybrid Encryption Adapter for CP-ABE (CP-ABE Hybrid)

Description: Converts a Ciphertext-Policy Attribute-Based Encryption scheme into a hybrid encryption scheme capable of encrypting arbitrary-length messages.

Notes: Uses symmetric encryption (AES) with a randomly generated session key.

The session key is encrypted using the underlying CP-ABE scheme.

Adapter Properties

• Type: hybrid encryption adapter

• Underlying Scheme: any Ciphertext-Policy ABE scheme

• Purpose: enables CP-ABE schemes to encrypt arbitrary-length byte messages

Implementation

Authors:

10. Ayo Akinyele

Date:

2011

class abenc_adapt_hybrid.HybridABEnc(scheme, groupObj)

Bases: ABEnc

>>> group = PairingGroup("SS512")
>>> cpabe = CPabe_BSW07(group)
>>> hyb_abe = HybridABEnc(cpabe, group)
>>> access_policy = '((four or three) and (two or one))'
>>> msg = b"hello world this is an important message."
>>> (master_public_key, master_key) = hyb_abe.setup()
>>> secret_key = hyb_abe.keygen(master_public_key, master_key, ['ONE', 'TWO', 'THREE'])
>>> cipher_text = hyb_abe.encrypt(master_public_key, msg, access_policy)
>>> hyb_abe.decrypt(master_public_key, secret_key, cipher_text)
b'hello world this is an important message.'

decrypt(pk, sk, ct)

encrypt(pk, M, object)

keygen(pk, mk, object)

setup()

abenc_adapt_hybrid.main()