def test_paillier_key_generation(self):
key = paillier.generate_keys(bits = 128)
public = key.public()
ptxt_original = 521
ctxt = paillier.encrypt(public, ptxt_original)
ptxt = paillier.decrypt(key, ctxt)
self.assertEqual(ptxt_original, ptxt)
# test homomorphism
ptxt1 = 14
ptxt2 = 19
ctxt1 = paillier.encrypt(public, ptxt1)
ctxt2 = paillier.encrypt(public, ptxt2)
final_ptxt = paillier.decrypt(key, ctxt1 * ctxt2)
self.assertEqual(final_ptxt, ptxt1 + ptxt2)
# test average
ptxt3 = 12
ctxt3 = paillier.encrypt(public, ptxt3)
ciphertext = [ctxt1, ctxt2, ctxt3]
numerator, denominator = paillier.average(public, ciphertext)
numerator = paillier.decrypt(key, numerator)
denominator = paillier.decrypt(key, denominator)
average = numerator/denominator
self.assertAlmostEqual(average, 15)
def average(request):
params = request.QUERY_PARAMS.dict()
# get the paillier key
modulus = params.pop('modulus', None)
generator = params.pop('generator', None)
if modulus is None or generator is None:
raise PubKeyRequired
try:
modulus = int(modulus)
generator = int(generator)
except ValueError:
raise PubKeyRequired("invalid public key")
key = paillier.PublicKey(modulus, generator)
packets = Packet.objects.encrypted_filter(**params)
try:
lengths = [int(packet.length) for packet in packets]
except ValueError:
raise APIException("invalid database state -- non-int packet lengths")
ctxt_sum, ctxt_count = paillier.average(key, lengths)
return Response({'sum': ctxt_sum, 'count': ctxt_count})
def average(request):
params = request.QUERY_PARAMS.dict()
# get the paillier key
modulus = params.pop('modulus', None)
generator = params.pop('generator', None)
if modulus is None or generator is None:
raise PubKeyRequired
try:
modulus = int(modulus)
generator = int(generator)
except ValueError:
raise PubKeyRequired("invalid public key")
key = paillier.PublicKey(modulus, generator)
packets = Packet.objects.encrypted_filter(**params)
try:
lengths = [int(packet.length) for packet in packets]
except ValueError:
raise APIException("invalid database state -- non-int packet lengths")
ctxt_sum, ctxt_count = paillier.average(key, lengths)
return Response({'sum': ctxt_sum, 'count': ctxt_count})
