# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import absolute_import, division, print_function
import pytest
import six
from cryptography.hazmat.primitives import padding
class TestPKCS7(object):
@pytest.mark.parametrize("size", [127, 4096, -2])
def test_invalid_block_size(self, size):
with pytest.raises(ValueError):
padding.PKCS7(size)
@pytest.mark.parametrize(("size", "padded"), [
(128, b"1111"),
(128, b"1111111111111111"),
(128, b"111111111111111\x06"),
(128, b""),
(128, b"\x06" * 6),
(128, b"\x00" * 16),
])
def test_invalid_padding(self, size, padded):
unpadder = padding.PKCS7(size).unpadder()
with pytest.raises(ValueError):
unpadder.update(padded)
unpadder.finalize()
def test_non_bytes(self):
padder = padding.PKCS7(128).padder()
with pytest.raises(TypeError):
padder.update(six.u("abc"))
unpadder = padding.PKCS7(128).unpadder()
with pytest.raises(TypeError):
unpadder.update(six.u("abc"))
@pytest.mark.parametrize(("size", "unpadded", "padded"), [
(
128,
b"1111111111",
b"1111111111\x06\x06\x06\x06\x06\x06",
),
(
128,
b"111111111111111122222222222222",
b"111111111111111122222222222222\x02\x02",
),
(
128,
b"1" * 16,
b"1" * 16 + b"\x10" * 16,
),
(
128,
b"1" * 17,
b"1" * 17 + b"\x0F" * 15,
)
])
def test_pad(self, size, unpadded, padded):
padder = padding.PKCS7(size).padder()
result = padder.update(unpadded)
result += padder.finalize()
assert result == padded
@pytest.mark.parametrize(("size", "unpadded", "padded"), [
(
128,
b"1111111111",
b"1111111111\x06\x06\x06\x06\x06\x06",
),
(
128,
b"111111111111111122222222222222",
b"111111111111111122222222222222\x02\x02",
),
])
def test_unpad(self, size, unpadded, padded):
unpadder = padding.PKCS7(size).unpadder()
result = unpadder.update(padded)
result += unpadder.finalize()
assert result == unpadded
def test_use_after_finalize(self):
padder = padding.PKCS7(128).padder()
b = padder.finalize()
with pytest.raises(ValueError):
padder.update(b"")
with pytest.raises(ValueError):
padder.finalize()
unpadder = padding.PKCS7(128).unpadder()
unpadder.update(b)
unpadder.finalize()
with pytest.raises(ValueError):
unpadder.update(b"")
with pytest.raises(ValueError):
unpadder.finalize()