#
#  SelfTest/Cipher/CAST.py: Self-test for the CAST-128 (CAST5) cipher
#
# Written in 2008 by Dwayne C. Litzenberger <dlitz@dlitz.net>
#
# ===================================================================
# The contents of this file are dedicated to the public domain.  To
# the extent that dedication to the public domain is not available,
# everyone is granted a worldwide, perpetual, royalty-free,
# non-exclusive license to exercise all rights associated with the
# contents of this file for any purpose whatsoever.
# No rights are reserved.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
# ===================================================================

"""Self-test suite for Crypto.Cipher.CAST"""

import pytest

from Crypto.Cipher import CAST
from Crypto.SelfTest.Cipher.common import make_block_tests

# This is a list of (plaintext, ciphertext, key) tuples.
test_data = [
    # Test vectors from RFC 2144, B.1
    ("0123456789abcdef", "238b4fe5847e44b2", "0123456712345678234567893456789a", "128-bit key"),
    ("0123456789abcdef", "eb6a711a2c02271b", "01234567123456782345", "80-bit key"),
    ("0123456789abcdef", "7ac816d16e9b302e", "0123456712", "40-bit key"),
]


class TestKeyLength:
    def test(self):
        with pytest.raises(ValueError):
            CAST.new(bytes([0]) * 4, CAST.MODE_ECB)
        with pytest.raises(ValueError):
            CAST.new(bytes([0]) * 17, CAST.MODE_ECB)


class TestOutput:
    def test(self):
        # Encrypt/Decrypt data and test output parameter

        cipher = CAST.new(b"4" * 16, CAST.MODE_ECB)

        pt = b"5" * 16
        ct = cipher.encrypt(pt)

        output = bytearray(16)
        res = cipher.encrypt(pt, output=output)
        assert ct == output
        assert res is None

        res = cipher.decrypt(ct, output=output)
        assert pt == output
        assert res is None

        output = memoryview(bytearray(16))
        cipher.encrypt(pt, output=output)
        assert ct == output

        cipher.decrypt(ct, output=output)
        assert pt == output

        with pytest.raises(TypeError):
            cipher.encrypt(pt, output=b"0" * 16)
        with pytest.raises(TypeError):
            cipher.decrypt(ct, output=b"0" * 16)

        shorter_output = bytearray(7)
        with pytest.raises(ValueError):
            cipher.encrypt(pt, output=shorter_output)
        with pytest.raises(ValueError):
            cipher.decrypt(ct, output=shorter_output)


TestVectors = make_block_tests(CAST, "CAST", test_data)