"""
Test whether layer 4 parsing and generating works
"""
import unittest
from ipaddress import IPv6Address
from dhcpkit_vpp.protocols.layer3 import IPv6
from dhcpkit_vpp.protocols.layer4 import UDP, UnknownLayer4Protocol
from dhcpkit_vpp.tests.protocols import FrameTestCase
[docs]class UnknownLayer4ProtocolTestCase(FrameTestCase):
[docs] def setUp(self):
self.packet_class = UnknownLayer4Protocol
self.packet_fixture = b'Demo packet'
self.message_fixture = UnknownLayer4Protocol(
data=b'Demo packet'
)
self.parse_packet()
[docs] def test_length(self):
self.assertEqual(self.message_fixture.length, len(self.packet_fixture))
self.assertEqual(self.message.length, len(self.packet_fixture))
self.assertEqual(self.message.length, len(self.packet_fixture))
self.assertEqual(self.length, len(self.packet_fixture))
[docs]class UDPTestCase(FrameTestCase):
[docs] def setUp(self):
self.packet_class = UDP
# Intentionally using odd number of bytes to test padding
self.packet_fixture = bytes.fromhex('123456780017a6b8') + b'Demo UDP packet'
self.message_fixture = UDP(
source_port=4660,
destination_port=22136,
checksum=42680,
payload=b'Demo UDP packet'
)
self.parse_packet()
[docs] def test_checksum_calculation(self):
dummy_ipv6 = IPv6(
source=IPv6Address('2001:9e0::3:2002'),
destination=IPv6Address('2001:9e0:4:32:212:45:32:0222'),
)
self.assertEqual(self.message_fixture.checksum, self.message.calculate_checksum(dummy_ipv6))
[docs] def test_validate_source_port(self):
self.check_unsigned_integer_property('source_port', 16)
[docs] def test_validate_destination_port(self):
self.check_unsigned_integer_property('destination_port', 16)
[docs] def test_validate_checksum(self):
self.check_unsigned_integer_property('checksum', 16)
[docs] def test_validate_payload(self):
setattr(self.message, 'payload', 0.1)
with self.assertRaisesRegex(ValueError, 'bytes'):
self.message.validate()
setattr(self.message, 'payload', 0)
with self.assertRaisesRegex(ValueError, 'bytes'):
self.message.validate()
setattr(self.message, 'payload', 'Not bytes')
with self.assertRaisesRegex(ValueError, 'bytes'):
self.message.validate()
setattr(self.message, 'payload', b'Bytes!')
self.message.validate()
[docs] def test_udp_length(self):
with self.assertRaisesRegex(ValueError, '8 bytes'):
UDP.parse(bytes.fromhex('00010002000700'))
with self.assertRaisesRegex(ValueError, '8 bytes'):
UDP.parse(bytes.fromhex('0001000200070000'))
UDP.parse(bytes.fromhex('0001000200080000'))
with self.assertRaisesRegex(ValueError, 'longer than available buffer'):
UDP.parse(bytes.fromhex('0001000200090000'))
[docs] def test_save_zero_checksum(self):
saved = self.message_fixture.save(zero_checksum=True)
fixture = bytes.fromhex('1234567800170000') + b'Demo UDP packet'
self.assertEqual(saved, fixture)
[docs] def test_save_with_checksum_calculation(self):
dummy_ipv6 = IPv6(
source=IPv6Address('2001:9e0::3:2002'),
destination=IPv6Address('2001:9e0:4:32:212:45:32:0222'),
)
self.message.checksum = -1
saved = self.message.save(recalculate_checksum_for=dummy_ipv6)
self.assertEqual(saved, self.packet_fixture)
if __name__ == '__main__': # pragma: no cover
unittest.main()