def encrypt_ballot_and_cast(self, selection, size, the_url, p_uuid):
self.c.get(self.locations['logout'])
e = Election.objects.get(uuid=self.e_uuid)
rel_selection = to_relative_answers(selection, size)
encoded = gamma_encode(rel_selection, size, size)
plaintext = algs.EGPlaintext(encoded, e.public_key)
randomness = algs.Utils.random_mpz_lt(e.public_key.q)
cipher = e.public_key.encrypt_with_r(plaintext, randomness, True)
modulus, generator, order = e.zeus.do_get_cryptosystem()
enc_proof = prove_encryption(modulus, generator, order, cipher.alpha,
cipher.beta, randomness)
r = self.c.get(the_url, follow=True)
self.assertEqual(r.status_code, 200)
cast_data = {}
##############
ballot = {
'election_hash': 'foobar',
'election_uuid': e.uuid,
'answers': [{
'encryption_proof': enc_proof,
'choices': [{
'alpha': cipher.alpha,
'beta': cipher.beta}]
}]
}
##############
enc_vote = datatypes.LDObject.fromDict(
ballot, type_hint='phoebus/EncryptedVote').wrapped_obj
cast_data['encrypted_vote'] = enc_vote.toJSON()
r = self.c.post('/elections/%s/polls/%s/cast'
% (self.e_uuid, p_uuid), cast_data)
voter = self.get_voter_from_url(the_url)
p = Poll.objects.get(uuid=p_uuid)
self.verbose('+ Voter %s voting at poll %s' % (voter.name, p.name))
return r
def generate_vote(p, g, q, y, choices, nr_candidates=None):
if isinstance(choices, int):
nr_candidates = choices
selection = get_random_selection(nr_candidates, full=0)
else:
nr_candidates = nr_candidates or (max(choices) if choices else 0) + 1
selection = to_relative_answers(choices, nr_candidates)
encoded = gamma_encode(selection, nr_candidates)
ct = encrypt(encoded, p, g, q, y)
alpha, beta, rand = ct
proof = prove_encryption(p, g, q, alpha, beta, rand)
commitment, challenge, response = proof
answer = {}
answer['encryption_proof'] = (commitment, challenge, response)
answer['choices'] = [{'alpha': alpha, 'beta': beta}]
encrypted_vote = {}
encrypted_vote['answers'] = [answer]
encrypted_vote['election_uuid'] = ''
encrypted_vote['election_hash'] = ''
return encrypted_vote, encoded, rand
def generate_vote(p, g, q, y, choices):
if isinstance(choices, int):
nr_candidates = choices
selection = get_random_selection(nr_candidates, full=0)
else:
nr_candidates = (max(choices) if choices else 0) + 1
selection = to_relative_answers(choices, nr_candidates)
encoded = gamma_encode(selection, nr_candidates)
ct = encrypt(encoded, p, g, q, y)
alpha, beta, rand = ct
proof = prove_encryption(p, g, q, alpha, beta, rand)
commitment, challenge, response = proof
answer = {}
answer['encryption_proof'] = (commitment, challenge, response)
answer['choices'] = [{'alpha': alpha, 'beta': beta}]
encrypted_vote = {}
encrypted_vote['answers'] = [answer]
encrypted_vote['election_uuid'] = ''
encrypted_vote['election_hash'] = ''
return encrypted_vote, encoded, rand