pksig_chch

Cha-Cheon Identity-Based Signature (CHCH03)

Authors: J. C. Cha, J. H. Cheon

Title: “An Identity-Based Signature from Gap Diffie-Hellman Groups”

Published in: PKC, 2003

Available from: LNCS Vol. 2567, pages 18-30

Notes:

Scheme Properties

• Type: signature (identity-based)

• Setting: bilinear groups (asymmetric)

• Assumption: Gap-DH

Implementation

Authors:

10. Ayo Akinyele

Date:

11/2011

class pksig_chch.CHCH(groupObj)

Bases: PKSig

>>> from charm.toolbox.pairinggroup import PairingGroup
>>> group = PairingGroup('SS512')
>>> chch = CHCH(group)
>>> (master_public_key, master_secret_key) = chch.setup()
>>> ID = "janedoe@email.com"
>>> (public_key, secret_key) = chch.keygen(master_secret_key, ID)  
>>> msg = "this is a message!" 
>>> signature = chch.sign(public_key, secret_key, msg)
>>> chch.verify(master_public_key, public_key, msg, signature)
True

keygen(msk, ID)

setup()

sign(pk, sk, M)

verify(mpk, pk, M, sig)

pksig_chch.main()