+from vpp_ip_route import VppIpRoute, VppRoutePath, FibPathProto
+
+# 35 is enough to have >257 400-byte fragments
+test_packet_count = 35
+
+# <class 'scapy.layers.inet.IP'>
+# <class 'scapy.layers.inet6.IPv6'>
+_scapy_ip_family_types = (IP, IPv6)
+
+
+def validate_scapy_ip_family(scapy_ip_family):
+
+ if scapy_ip_family not in _scapy_ip_family_types:
+ raise ValueError("'scapy_ip_family' must be of type: %s. Got %s" %
+ (_scapy_ip_family_types, scapy_ip_family))
+
+
+class TestIPReassemblyMixin(object):
+
+ def verify_capture(self, scapy_ip_family, capture,
+ dropped_packet_indexes=None):
+ """Verify captured packet stream.
+
+ :param list capture: Captured packet stream.
+ """
+ validate_scapy_ip_family(scapy_ip_family)
+
+ if dropped_packet_indexes is None:
+ dropped_packet_indexes = []
+ info = None
+ seen = set()
+ for packet in capture:
+ try:
+ self.logger.debug(ppp("Got packet:", packet))
+ ip = packet[scapy_ip_family]
+ udp = packet[UDP]
+ payload_info = self.payload_to_info(packet[Raw])
+ packet_index = payload_info.index
+ self.assertTrue(
+ packet_index not in dropped_packet_indexes,
+ ppp("Packet received, but should be dropped:", packet))
+ if packet_index in seen:
+ raise Exception(ppp("Duplicate packet received", packet))
+ seen.add(packet_index)
+ self.assertEqual(payload_info.dst, self.src_if.sw_if_index)
+ info = self._packet_infos[packet_index]
+ self.assertTrue(info is not None)
+ self.assertEqual(packet_index, info.index)
+ saved_packet = info.data
+ self.assertEqual(ip.src, saved_packet[scapy_ip_family].src)
+ self.assertEqual(ip.dst, saved_packet[scapy_ip_family].dst)
+ self.assertEqual(udp.payload, saved_packet[UDP].payload)
+ except Exception:
+ self.logger.error(ppp("Unexpected or invalid packet:", packet))
+ raise
+ for index in self._packet_infos:
+ self.assertTrue(index in seen or index in dropped_packet_indexes,
+ "Packet with packet_index %d not received" % index)
+
+ def test_disabled(self, scapy_ip_family, stream,
+ dropped_packet_indexes):
+ """ reassembly disabled """
+ validate_scapy_ip_family(scapy_ip_family)
+ is_ip6 = 1 if scapy_ip_family == IPv6 else 0
+
+ self.vapi.ip_reassembly_set(timeout_ms=1000, max_reassemblies=0,
+ max_reassembly_length=1000,
+ expire_walk_interval_ms=10000,
+ is_ip6=is_ip6)
+
+ self.pg_enable_capture()
+ self.src_if.add_stream(stream)
+ self.pg_start()
+
+ packets = self.dst_if.get_capture(
+ len(self.pkt_infos) - len(dropped_packet_indexes))
+ self.verify_capture(scapy_ip_family, packets, dropped_packet_indexes)
+ self.src_if.assert_nothing_captured()
+
+ def test_duplicates(self, scapy_ip_family, stream):
+ """ duplicate fragments """
+ validate_scapy_ip_family(scapy_ip_family)
+
+ self.pg_enable_capture()
+ self.src_if.add_stream(stream)
+ self.pg_start()
+
+ packets = self.dst_if.get_capture(len(self.pkt_infos))
+ self.verify_capture(scapy_ip_family, packets)
+ self.src_if.assert_nothing_captured()
+
+ def test_random(self, scapy_ip_family, stream):
+ """ random order reassembly """
+ validate_scapy_ip_family(scapy_ip_family)
+
+ fragments = list(stream)
+ shuffle(fragments)
+
+ self.pg_enable_capture()
+ self.src_if.add_stream(fragments)
+ self.pg_start()
+
+ packets = self.dst_if.get_capture(len(self.packet_infos))
+ self.verify_capture(scapy_ip_family, packets)
+ self.src_if.assert_nothing_captured()
+
+ # run it all again to verify correctness
+ self.pg_enable_capture()
+ self.src_if.add_stream(fragments)
+ self.pg_start()
+
+ packets = self.dst_if.get_capture(len(self.packet_infos))
+ self.verify_capture(scapy_ip_family, packets)
+ self.src_if.assert_nothing_captured()
+
+ def test_reassembly(self, scapy_ip_family, stream):
+ """ basic reassembly """
+ validate_scapy_ip_family(scapy_ip_family)
+
+ self.pg_enable_capture()
+ self.src_if.add_stream(stream)
+ self.pg_start()
+
+ packets = self.dst_if.get_capture(len(self.pkt_infos))
+ self.verify_capture(scapy_ip_family, packets)
+ self.src_if.assert_nothing_captured()
+
+ # run it all again to verify correctness
+ self.pg_enable_capture()
+ self.src_if.add_stream(stream)
+ self.pg_start()
+
+ packets = self.dst_if.get_capture(len(self.pkt_infos))
+ self.verify_capture(scapy_ip_family, packets)
+ self.src_if.assert_nothing_captured()
+
+ def test_reversed(self, scapy_ip_family, stream):
+ """ reverse order reassembly """
+ validate_scapy_ip_family(scapy_ip_family)
+
+ fragments = list(stream)
+ fragments.reverse()
+
+ self.pg_enable_capture()
+ self.src_if.add_stream(fragments)
+ self.pg_start()
+
+ packets = self.dst_if.get_capture(len(self.packet_infos))
+ self.verify_capture(scapy_ip_family, packets)
+ self.src_if.assert_nothing_captured()
+
+ # run it all again to verify correctness
+ self.pg_enable_capture()
+ self.src_if.add_stream(fragments)
+ self.pg_start()